The invention relates generally to a device for measuring torque on a rotating shaft and more particularly to a device which measures the angular displacement of two magnets relative to each other. The invention also pertains to a device for measuring the rotational speed of the shaft and the power transmitted by it.
French Patent No. Fr-A-2,626,368 describes a device in which the angular position of two magnets is sensed by an "all or nothing" signal output sensor. The torsional moment of the shaft is determined from the phase shift of signals from the two sensors. This device does not, however, permit the measurement of the torque on a shaft even when the shaft is blocked or when its speed is changing.
The foregoing illustrates limitations known to exist in present torque sensors. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided, including features more fully disclosed hereinafter.